(MORGAN COUNTY) - A Morgan County judge sentenced 29-year-old Amanda Vandagrifft to six months behind bars for the shooting death of her 6-year-old son back in June 2011.

Vandagrifft's then 11-year-old son shot and killed his little brother Andrew Frye in their Martinsville home.

Vandagrifft and her boyfriend, now husband, were not home at the time of the shooting.

Prosecutors say the mom failed to lock up her .22-caliber rifle and ammunition before leaving home to go on a wrecker run.

According to court documents, the 11-year-old held knives to his siblings' throats, threatening to kill them if they didn't do what they were told. The report also said just the week before he had loaded a long rifle and used it to threaten the younger kids, showing them the bullets were in the chambers.

According to court documents, the lead detective in the case said the 11-year-old intially told police the 6-year-old shot himself and had earlier said he would kill himself. Upon further questioning with his parents present, however, the boy told police he had been threatening Andrew with the gun after Andrew refused to clean their room, and shot him in the head. He told police he didn't know the gun was loaded.

The boy told police he then returned the gun to his mother's room, where it was kept, and called 911 to report the shooting

Court documents also report Vandagrifft was aware of past violence done by the 11-year-old to family members, as well as students at his school.

"The weapon was in (her) bedroom, the ammunition was in (her) bedroom, nothing was locked up," said Morgan County Prosecutor Steve Sonnega.

Before final sentencing, Judge Thomas Gray chastised Vandagrifft saying: "Society demands we not leave our children alone ... You didn't grasp the reality you neglected your children. Andrew (your son) is dead. I'll agree you didn't pull the trigger, but you didn't do anything to stop it either."

Vandagrifft faced up to 14 years behind bars. The judge sentenced her to eight years but suspended all but six months. She will serve that time in the Morgan County Jail.

Vandagrifft will also serve two years of home detention and eight years probation.

This summer, her husband, Matthew Boulden, pleaded guilty for his role and was sentenced to just one day in prison.

Vandagrifft had pleaded guilty to to one charge of neglect of a dependent after her son fatally shot his brother in June 2011.